From: Yauheni Kaliuta <yauheni.kaliuta@xxxxxxxxxx> [ Upstream commit c210773d6c6f595f5922d56b7391fe343bc7310e ] The error path in libbpf.c:load_program() has calls to pr_warn() which ends up for global_funcs tests to test_global_funcs.c:libbpf_debug_print(). For the tests with no struct test_def::err_str initialized with a string, it causes call of strstr() with NULL as the second argument and it segfaults. Fix it by calling strstr() only for non-NULL err_str. Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@xxxxxxxxxx> Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> Acked-by: Yonghong Song <yhs@xxxxxx> Link: https://lore.kernel.org/bpf/20200820115843.39454-1-yauheni.kaliuta@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/testing/selftests/bpf/prog_tests/test_global_funcs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c index 25b068591e9a4..193002b14d7f6 100644 --- a/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c +++ b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c @@ -19,7 +19,7 @@ static int libbpf_debug_print(enum libbpf_print_level level, log_buf = va_arg(args, char *); if (!log_buf) goto out; - if (strstr(log_buf, err_str) == 0) + if (err_str && strstr(log_buf, err_str) == 0) found = true; out: printf(format, log_buf); -- 2.25.1